No abstract

No abstract

Contents:IJES is a refereed international journal providing an international forum to report, discuss and exchange experimental or theoretical results, novel designs, work-in-progress, experience, case studies, and trend-setting ideas. Papers should be of a quality that represents the latest advances in embedded systems in time-to-market, cost, code size, weight, testability, power, real-time behaviour, and stimulating future trends.

Biclique cryptanalysis is a typical attack through finding a biclique which is a type of bipartite diagram to reduce the computational complexity. By investigating the subkey distribution and the encryption structure, we find out a weakness in the key schedule of Piccolo-80. A 6-round biclique is constructed for Piccolo-80 and a 7-round biclique for Piccolo-128. Then a full round biclique cryptanalysis of Piccolo is presented. The results of the attacks are with data complexity of 2 40 and 2 24 chosen ciphertexts and with computational complexity of 2 79.22 and 2 127.14 , respectively. They are superior to other known results of biclique cryptanalytic on Piccolo.

Mixed integer linear programming (MILP) model was presented by Sun et al. at Asiacrypt 2014 to search for differential characteristics of block ciphers. Based on this model, it is easy to assess block ciphers against differential attack. In this paper, the MILP model is improved to search for differential trails of Midori64 which is a family of lightweight block ciphers provided by Banik et al. at Asiacrypt 2015. We find the best 5-round differential characteristics of Midori64 with MILP-based model, and the probabilities are 2 −52 and 2 −58 respectively. Based on these distinguishers, we give key recovery attacks on the 11-round reduced Midori64 with data complexities of 2 55.6 and 2 61.2 , and time complexities of 2 109.35 and 2 100.26. INDEX TERMS Midori, differential distinguisher, mixed integer linear programming, differential cryptanalysis.

No abstract

No abstract

In this paper, a new method for constructing a Mixed Integer Linear Programming (MILP) model on conditional differential cryptanalysis of the nonlinear feedback shift register-(NLFSR-) based block ciphers is proposed, and an approach to detecting the bit with a strongly biased difference is provided. The model is successfully applied to the block cipher KATAN32 in the single-key scenario, resulting in practical key-recovery attacks covering more rounds than the previous. In particular, we present two distinguishers for 79 and 81 out of 254 rounds of KATAN32. Based on the 81-round distinguisher, we recover 11 equivalent key bits of 98-round KATAN32 and 13 equivalent key bits of 99-round KATAN32. The time complexity is less than 2 31 encryptions of 98-round KATAN32 and less than 2 33 encryptions of 99-round KATAN32, respectively. Thus far, our results are the best known practical key-recovery attacks for the round-reduced variants of KATAN32 regarding the number of rounds and the time complexity. All the results are verified experimentally.